CVE-2023-42818

criticalpriority · track · 39EPSS 0.007 · 52 %ileEURUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

0.68% (52nd) EPSS

CVSS 9.8 · critical

Is it mine?

9 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · fstec_bdu · osv

EPSS · scored 2026-10-26

JumpServer is an open source bastion host. When users enable MFA and use a public key for authentication, the Koko SSH server does not verify the corresponding SSH private key. An attacker could exploit a vulnerability by utilizing a disclosed public key to attempt brute-force authentication against the SSH service This issue has been patched in versions 3.6.5 and 3.5.6. Users are advised to upgrade. There are no known workarounds for this issue.

cvss

Technical severity, 0–10. One row per scoring source.

9.8

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–critical · 5.4–9.8

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 5.9

v3.19.8criticalAV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU

v3.15.4mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:Lsecondary · ENISA EU

v3.15.4mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:Lsecondary · security-advisories@github.comexploitability 2.8 · impact 2.5

v3.19criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: poc · Automatable: no · Technical Impact: partialcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-307USprimaryCWE-287USCWE-287USCWE-307US

affected products (9)

Products and version ranges known to be affected.

jumpserver jumpserver≤ < 3.5.6enisa_euvdEU
jumpserver jumpserver3.6.0, → 3.6.5enisa_euvdEU
Hangzhou Feizhiyun Information Technology Co., Ltd. JumpServer≤ 3.5.6fstec_bduRU
Hangzhou Feizhiyun Information Technology Co., Ltd. JumpServer3.6.0 → 3.6.5fstec_bduRU
fit2cloud jumpserver< 3.5.6nvdUScpe:2.3:a:fit2cloud:jumpserver:*:*:*:*:*:*:*:*
fit2cloud jumpserver3.6.0 → 3.6.5nvdUScpe:2.3:a:fit2cloud:jumpserver:*:*:*:*:*:*:*:*
Go github.com/jumpserver/jumpserver< 3.5.6+incompatibleosvUSpkg:golang/github.com/jumpserver/jumpserver
Go github.com/jumpserver/jumpserver3.6.0+incompatible → 3.6.5+incompatibleosvUSpkg:golang/github.com/jumpserver/jumpserver
Go github.com/jumpserver/kokoall versionsosvUSpkg:golang/github.com/jumpserver/koko

advisories (1)

Vendor and ecosystem advisories describing this.

GO-2025-3570SSH public key login without private key challenge if mfa is enabled in jumpserver in github.com/jumpserver/koko in github.com/jumpserver/jumpserver2025-06-12vendor · osvUS
SSH public key login without private key challenge if mfa is enabled in jumpserver in github.com/jumpserver/koko in github.com/jumpserver/jumpserver

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu osv nvd NVD CVE.org MITRE

published 2023-09-27modified 2026-06-17

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+818 more

references (7)

External citations — patches, advisories, analysis.

scry

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